這里以Rockchip平臺(tái)為例，Rockchip平臺(tái)lcd timing常見參數(shù)配置如下：

disp_timings: display-timings {
    native-mode = <&timing0>;
    timing0: timing0 {
        clock-frequency = <31000000>;
        hactive = <480>;
        vactive = <854>;
        hback-porch = <24>;
        hfront-porch = <72>;
        vback-porch = <10>;
        vfront-porch = <12>;
        hsync-len = <24>;
        vsync-len = <2>;
        hsync-active = <0>;
        vsync-active = <0>;
        de-active = <0>;
        pixelclk-active = <0>;
    };
};

常規(guī)參數(shù)

其中以下參數(shù)根據(jù)屏的規(guī)格書填寫：

hactive = <480>;        // 分辨率-寬
vactive = <854>;        // 分辨率-高
hback-porch = <24>;     // 行可視范圍前肩
hfront-porch = <72>;    // 行可視范圍后肩
vback-porch = <10>;     // 幀可視前肩
vfront-porch = <12>;    // 幀可視后肩
hsync-len = <24>;       // 行同步肪沖寬度
vsync-len = <2>;        // 場(chǎng)同步脈沖寬度

以下參數(shù)表示對(duì)應(yīng)信號(hào)的有效電平，默認(rèn)為低電平（0）：

hsync-active = <0>;     // 行同步信號(hào)
vsync-active = <0>;     // 場(chǎng)同步信號(hào)
de-active = <0>;        // de信號(hào)
pixelclk-active = <0>;  // clk信號(hào)

clock-frequency 的計(jì)算方法

已知下面參數(shù)：

• fps: 屏幕刷新率（默認(rèn)：60幀）
• htotal: hactive + hback-porch + hfront-porch + hsync-len
• vtotal: vactive + hfront-porch + vfront-porch + vsync-len

求clock-frequency公式如下：

htotal * vtotal * fps = clock-frequency

按照上面參考參數(shù)計(jì)算如下：

(480 + 24 + 72 + 24) x (854 + 10 + 12 + 2) x 60 = 31608000

計(jì)算出來(lái)的準(zhǔn)確值為31608000，我們?nèi)≌?/p>

clock-frequency = <31000000>;

dsi_hs_clk 的計(jì)算方法

100 + ((htotal * vtotal * fps) * 3 * 8 / lanes)